Pushrod ?

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dodge71demon

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Doing a stock remanufactured 5.9 magnum long block for my A body decided on the Howard cam with 507/533 lift and Hughes valve springs etc using stock 1.6 rockers - pushrods and roller lifters ? is do you foresee and valve to piston clearance problems I don't think there should be really don't want to pull heads to check even though I know it's better to safe than sorry anybody use this cam
 
Doing a stock remanufactured 5.9 magnum long block for my A body decided on the Howard cam with 507/533 lift and Hughes valve springs etc using stock 1.6 rockers - pushrods and roller lifters ? is do you foresee and valve to piston clearance problems I don't think there should be really don't want to pull heads to check even though I know it's better to safe than sorry anybody use this cam

If the cam itself has 507/533 and then using a 1.6 rocker, then yes I would be concerned.
The spring retainers could even hit the stem seals or stem guides if those are not modified.
 
But r u willing to take that chance. It gets a whole lot more expensive if it doesn’t work out. I do notice though on threads like this no matter how many say to check it that as soon as someone says what u want to hear ur good to go. Possibly. Don’t take any short cuts. Thats the difference between mechanics and wanna be mechanics. Kim
 
But r u willing to take that chance. It gets a whole lot more expensive if it doesn’t work out. I do notice though on threads like this no matter how many say to check it that as soon as someone says what u want to hear ur good to go. Possibly. Don’t take any short cuts. Thats the difference between mechanics and wanna be mechanics. Kim

100% correct have all winter and just a set of head gaskets
 
way up north - central

Ok. I am in sullivan county. I have a couple hyd. roller lifters I just made solid for checking piston to valve clearance. I was going to tell you to swing by and borrow them if you were close.
I could mail them to you when the time comes if you'll mail them back. They are not hard to make if you have a couple spare lifters.
 
Ok. I am in sullivan county. I have a couple hyd. roller lifters I just made solid for checking piston to valve clearance. I was going to tell you to swing by and borrow them if you were close.
I could mail them to you when the time comes if you'll mail them back. They are not hard to make if you have a couple spare lifters.
Hey Sam,
Question for you. When using these, how do you account for the amount of preload that will be put on the actual hydraulic lifters when everything is assembled? Or do you just tighten the rocker pivot down just enough to take up the slack and no more?
 
Hey Sam,
Question for you. When using these, how do you account for the amount of preload that will be put on the actual hydraulic lifters when everything is assembled? Or do you just tighten the rocker pivot down just enough to take up the slack and no more?

Adjustable pushrod
 
You can check it assembled, set up a cylinder adjust lash, replace the valve springs with light checker springs. slowly rotate motor by hand until it is on the exhaust stroke. As the piston comes up stop every 5 degrees and push down on valve. Use feeler gauge to check piston to valve clearance. Turn it another 5 degrees and repeat until the piston reaches tdc and starts to go back down . Continue for 20-30 degrees atdc. There you go. If it wont turn your have your answer. You can check both valves but the exhaust is the concern.
 
do not just adjust the rockers
get mid lift rocker adjustment then use an adjustable pushrod
reason
if rocker height is set low then the rocker is angled up more when on the seat
and angled down less at full lift
the rocker ratio is maximum when the rocker axis is perpendicular to the valve
in this case that is when the valve is more open
more ratio give you more lift and less piston clearance
this is with either roller or stock rockers
totally not right as you have higher acceleration of the valve when the cam is trying to go over the top- easier valve float
do it right
 
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You can check it assembled, set up a cylinder adjust lash, replace the valve springs with light checker springs. slowly rotate motor by hand until it is on the exhaust stroke. As the piston comes up stop every 5 degrees and push down on valve. Use feeler gauge to check piston to valve clearance. Turn it another 5 degrees and repeat until the piston reaches tdc and starts to go back down . Continue for 20-30 degrees atdc. There you go. If it wont turn your have your answer. You can check both valves but the exhaust is the concern.
Generally good IMHO. My only concern with that is if the checker springs and the hydraulic lifter spring are close to the same rate pressures, then as you compress the checker spring, they might start to move the hydraulic lifter piston down and thus won't lift the valve completely. So very light checker springs, IMHO.
As for the exhaust only... what if the cam has the same intake and exhaust lift and is not ground or set advanced? If the eyebrows, are the same depth, then I'd expect the intake to be closer.....

do not just adjust the rockers
get mid lift rocker adjustment then use an adjustable pushrod
reason
if rocker height is set low then the rocker is angled up more when on the seat
and angled down less at full lift
the rocker ratio is maximum when the rocker axis is perpendicular to the valve
in this case that is when the valve is more open
more ratio give you more lift and less piston clearance
this is with either roller or stock rockers
I got that... if the clearance was liberal, then I'd not worry about that. If it was close, then, yes, time to do it as precisely as possilbe.
 
Piston is running away from the opening intake valve. Piston is going towards the open exhaust valve. So “usually” if a valve hits its the exhaust. You can just try to bleed down the hydr lifter so it is bottomed out then adjust to zero lash or get a solid lifter. You definitely need to be able to visualize what is going on and pay attention to the details, but it can be done.
 
you need to do to get the right pushrods as well as valve clearance
especially with a reground cam or different than stock base circle
if ground on a new billet a higher lift cam the additional lift is all on the valve open side so pushrod will be different than stock
 
Ok. I am in sullivan county. I have a couple hyd. roller lifters I just made solid for checking piston to valve clearance. I was going to tell you to swing by and borrow them if you were close.
I could mail them to you when the time comes if you'll mail them back. They are not hard to make if you have a couple spare lifters.
Thanks and interested in your fine offer
 
I just sent you a PM, maybe it will let you respond to it. I will be leaving shortly, it will be late tonight before I can respond.
 
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